1. Field of the Invention
The present invention relates to quick release camming mechanisms such as for retaining a bicycle wheel hub to the front fork and rear drop-out of a bicycle, to retaining a seat post to the seat tube of a bicycle frame, and, more particularly, to quick release devices that can be difficult to open or close.
2. Background Art
Quick-release skewers are well-known and are used on the wheels and frames of better quality bicycles to facilitate their mounting on or removal from the bicycle frame. Quick release skewers use a quick release camming mechanism. Typically, a quick-release skewer comprises a shaft having threaded ends, a large nut on one end, and a camming mechanism on the other end. The hub engages the drop-out slots of a front fork or rear stays (of the frame) immediately inboard of the nut and camming mechanism, so that actuation of the camming mechanism causes the drop-outs to be clamped against the wheel hub. Riders oftentimes remove their wheels for better fitting their bicycle into their car for easier transportation. Riders also remove their wheels when repairing a flat tire or when replacing their tires. Riders also remove their front tire when locking up their bicycle. It is advantageous to have a quick release skewer that does not require tools for these purposes.
Quick release seat posts are also well-known and are used on many better quality off-road bicycles to facilitate quick height adjustment or installation and removal of the seat post relative to the bicycle frame. Quick release seat posts also use a quick release camming mechanism. Typically, a quick release seat post is a quick release clamp or ring that fits around the top of the frame's top tube in order to squeeze the frame top tube around the seat post. Typically, the top tube has a split to allow the clamp to more easily squeeze the top tube onto the seat post. Oftentimes, a rider wants to lower their seat post during steep descents (for safety and control) and raise their seat for other riding to increase their riding efficiency. Riders also oftentimes remove their seat post for better fitting their bicycle into their car for easier transportation, or to prevent the seat and seat post from being stolen. It is advantageous to have a quick release clamp that does not require tools for these purposes.
A disadvantage of conventional quick release skewers and quick release seat post clamps is that they are often difficult to close and open. To adequately clamp a hub or seat post, a certain amount of force is required to close the lever of the quick release. The amount of force may be excessive for people who do not possess great hand strength. Furthermore, the amount of force to release the quick release is, in some cases, even more than the original clamping force, if the quick release has remained in the closed position for a long time. In some cases, a person with strong hands tightens the quick release of a friend's bike, and that friend is later unable to remove their wheels or adjust their seat post. Furthermore, when pulling extremely hard on a quick release lever, the lever can suddenly release and slap the person's hand with painful force.
Quick release seat post clamps work much the same as quick release skewers. They can even share some of the same parts such as the lever and camming mechanism. Quick release seat post clamps present a similar problem as quick release skewers. That is, opening and closing the lever on their seat post clamp can be difficult. Depending on the exact dimensions, design, and material of the seat post and seat tube, it can require significant clamping force to adequately clamp the seat post to the seat tube. In some cases, a stronger rider must regularly assist weaker riders to open and close the seat post clamp. In other cases, a weaker rider may find that their seat post has slipped out of the desired position because they have not been able to apply enough force to the quick release lever.
It is highly desirable to have a skewer and seat post clamp that is easier to open and close, yet provides the same clamping force as conventional skewers and seat post clamps. In some cases, this would not only be a convenience, but allow weaker handed riders independence and confidence to ride on their own, without the worry of not being able to remove and install their wheel to fix a flat tire, or adjust their seat post height. This leads to a more enjoyable ride for many people.
It is also highly desirable to have an improved quick release camming mechanism for many other applications, related to bicycles and to other areas as well.
Accordingly, there is a need for a quick release mechanism that is easier to open and close, allowing for improved products such as a bicycle quick release skewer and a quick release seat post clamp.